[jamblewamble]

>Bloom et al. looked across many sectors, from agriculture to medicine to computing. In each field, productivity measures have grown at the same rate as before. This sounds like good news, except that the number of researchers in each of these fields has exploded. In other words, each researcher produces much less than they used to — something you might expect if ideas really are getting harder to find.

Each researcher produces less on average, but that is just restating the statistic in different terms.

I suspect the answer is just that increasing the number of people in a research field does not mean it produces more innovations. Almost all the big innovations are produced by a tiny number of people. Let's call them the geniuses. The geniuses of a field adore the field, were never going to study anything else, and would contribute to innovation no matter what. Everyone else just fiddles around the edges. That's why making PhD-level research much more accessible hasn't increased the amount of innovation even close to commensurately.

We now have tidier, cleaner theories. They cover more edge cases. They're neater. All the little side branches are investigated and filled in. But we aren't getting more big leaps.